Data from three cities shows that the feature is deterring thieves.

One of the new features iOS 7 introduced was an upgrade to the Find My iPhone service called Activation Lock—in addition to tracking your phone, sending it messages, and wiping your data, any iOS device with Find My iPhone enabled now requires your Apple ID to reactivate it. Even if your phone is stolen, the thief can't turn around and resell it as a new phone.

According to data from the Secure Our Smartphones Initiative group, the feature has apparently had a measurable effect on theft. Bloombergreports that for the first five months of 2014, iPhone theft in New York City, San Francisco, and London is down by 19, 38, and 24 percent respectively compared to the same period in 2013. New York Attorney General Eric Schneiderman says that iPhone theft "plummeted" following the release of iOS 7 in September.

Android and Windows Phone each have similar phone-tracking features to help people find lost or stolen phones, but their remote wipe features are less capable. Resetting an Android or Windows phone erases all of your personal data from the internal storage, but it simply resets the phone to its factory settings—it can then be reused or resold by the thief without any negative repercussions. You might even save the thief the trouble of manually wiping the phone.

Remotely wiping an Android phone will protect your data, but the device can still be used and resold.

Andrew Cunningham

Several states in the US are working on legislation that would make theft-deterring "kill switches" mandatory in smartphones, and various OEMs and carriers are already working to implement them. This Activation Lock data is a strong argument in favor of making kill switches universal.

The downside of these anti-theft "kill switches" is that they can damage the market for secondhand phones—a Verge report from earlier this month examined this in some depth, talking to several iPhone resellers who resorted to using locked iPhones for parts because the Activation Lock feature can't be bypassed. That means it's working as intended, but it also means that these resellers will need to make sure the iPhones they're getting have had Find My iPhone turned off before they take them.

Andrew Cunningham / Andrew has a B.A. in Classics from Kenyon College and has over five years of experience in IT. His work has appeared on Charge Shot!!! and AnandTech, and he records a weekly book podcast called Overdue.